A biopsy is carried out during a minimal-invasive surgery to determine the status of a suspicious lesion. Since the suspicious lesions must be visible for a surgeon, these biopsies are taken generally in a later stage of a disease. The biopsies are then sent to a pathologist to investigate target tissue sections. The outcome thus depends on the local tissue samples that could or could not represent the actual disease stage in the tissue. Optical biopsy is an alternative method, where in-vivo optical technology is used to determine whether the disease has affected the tissue. This method also enables the diagnosis of the disease in an early stage. Light can interact with the tissue in a number of ways, including elastic and inelastic (multiple or single) scattering, reflection of boundary layers and absorption, and can for instance lead to fluorescence and Raman scattering. All of these can be utilized to measure any abnormal change in the tissue. This is beneficial to a patient, because no tissue is removed and an analysis can be performed in real time on the spot at all necessary locations. Furthermore automatic diagnosis would save a lot of time for the patient as well as for the surgeon who can diagnose and treat the person instead of waiting for pathology results.
An optical biopsy device must fulfill two requirements to be useful. Firstly it must be able to scan a significant area within a limited time. Secondly, it must have a high sensitivity and specificity. Currently, various optical methods have been proposed for cancer detection. The methods, capable of screening larger areas (in general non-point-like methods) that are available, have high sensitivity but have a rather low specificity. Hence these methods produce a lot of false positives. Methods that have a much higher specificity are in general point like measuring methods. These methods can give a good diagnosis but are not suited to scan significant areas in a short period of time. To fulfill both the above-mentioned requirements, two different optical devices are required. One based on a “camera” like of imaging capable of viewing larger areas and another one based on a “microscope” like imaging capable of viewing tissue on a cellular level. It is apparent that the biopsy procedures would be more efficient and effective if a single optical biopsy device can switch between two different views of a target site without removing the device from the patient.
Although combining a camera and a microscope functions in one device have been described in patent application US20040158129, the two optical modalities are still separate entities placed aside of each other. This results in rather bulky devices. Since for minimal invasive procedures the width of the device is of utmost importance, such solutions as described in US20040158129 may not be preferable.
It would therefore be advantageous to have an optical biopsy device which does not have the disadvantage that is described above and more in particular to have a compact optical biopsy device that enables camera like (macroscopic) and microscope like imaging possible.
Particular and preferred aspects of the invention are set out in the accompanying independent and dependent claims. Features from the dependent claims may be combined with features of the independent claims and with features of other dependent claims as appropriate and not merely as explicitly set out in the claims.